Hair and scalp leave on treatment compositions comprising various combinations of hair and scalp actives, are known in the art and are commercially available. These compositions may have rheological properties that optimize the consumer perceived usage experience (non-dripping, spread, coverage, etc.).
Anti-dandruff hair rinse off products are also commercially available. Anti-dandruff shampoos, conditioners, and other rinse off treatments typically incorporate an anti-dandruff active. One type of anti-dandruff agents are particulate, crystalline anti-dandruff agents, such as sulfur, selenium disulfide and multi-valent metal salts of pyridinethione. Soluble anti-dandruff agents, such as ketoconazole, are also available.
Nevertheless, some consumers desire an anti-dandruff leave on treatment which provides a level of anti-dandruff efficacy that can replace other anti-dandruff rinse off products or is used in addition to rinse off anti-dandruff products or provide leave on benefits to hair and scalp that are difficult to achieve with a rinse off product. Consequently, a need exists for a treatment product that combines core anti-dandruff efficacy with additional scalp health and hair benefits that the consumer can notice and feel, i.e. effective, and is delightful to use.
The present invention involves a scalp-directed leave-on treatment with particulate active ingredient (ZPT) that is well dispersed without the use of high levels of volatile organic solvents. The exclusion of volatile organic solvents (e.g. ethanol) can typically cause agglomeration of the particulate active, via an interaction with insoluble hydrophobic components of the composition (e.g. perfume). This agglomeration can lead to a reduction in the efficacy of the product, as well as potential product stability issues. The use of low levels of certain solubilizing agents can mitigate this agglomeration.